Skip to content

Study · Animal study (in vivo) · rat · 2010

8 results

Intermittent MTII application evokes repeated anorexia and robust fat and weight loss.

Zhang Y, Collazo R, Gao Y, Li G, Scarpace PJ

Peptides23 Dec 2009Cited by 7 (Europe PMC)

PMID20034526 (opens in a new tab)PMCIDPMC2860181 (opens in a new tab)DOI10.1016/j.peptides.2009.12.019 (opens in a new tab)PepBankPUB-20034526
Source linkPubMedAsk about this study
Jump to 8 results

Summary

The text of this summary is not shown here, because the article license does not allow reuse. Read it at the source (opens in a new tab)

Text rights: Publisher copyright. Results still quote short attributed sentences.

Results from this study8

8 results from studies that gave the peptide. No result from this study comes from people.

  1. 01AnimalAnimal study (in vivo)Efficacy outcome

    In rats, the first lateral-ventricle MTII application reduced food intake by 30%, and this effect attenuated within 5 days.

    In plain wordsIn rats, the first dose of melanotan II into the brain cut food intake by 30%, but the effect faded within 5 days.

    Peptide
    Melanotan II
    Outcome
    DecreaseFood intake after first MTII application
    Study

    ratn: not reported in source

    F344/BN rats
    Comparator
    Vehicle
    Outcome group
    Appetite and food intake · Metabolic and weight
    Studied dose
    Dose not stated · intracerebroventricular (lateral ventricle, mini pump)As given in this study (rat).

    Measurements

    Food intake reduction
    30%
    first MTII application

    Source sentences

    Summary
    The first MTII application induced a 30% food reduction that attenuated within 5 days.
    1 context sentence
    Summary · context
    F344/BN rats were infused with MTII or vehicle into the lateral ventricle by mini pump for 14 days.
  2. 02AnimalAnimal study (in vivo)Efficacy outcome

    In rats, reapplying MTII after an off period caused a new and equally robust anorectic response.

    In plain wordsIn rats, giving melanotan II again after a break cut food intake as strongly as the first time.

    Peptide
    Melanotan II
    Outcome
    DecreaseFood intake after MTII reapplication following an off period
    Study

    ratn: not reported in source

    F344/BN rats
    Comparator
    Vehicle (control level)
    Outcome group
    Appetite and food intake · Metabolic and weight
    Studied dose
    Dose not stated · intracerebroventricular (lateral ventricle, mini pump)As given in this study (rat).

    Source sentences

    Summary
    Reapplication of MTII in MTII-On/Off rats, after the off period, invoked a new and equally robust anorectic response
    2 context sentences
    Summary · context
    Half the MTII-infused rats were then given vehicle (MTII-On/Off), while the remaining received fresh MTII (MTII-On) for 10 days.
    Summary · context
    F344/BN rats were infused with MTII or vehicle into the lateral ventricle by mini pump for 14 days.
  3. 03AnimalAnimal study (in vivo)Efficacy outcome

    In rats, continued MTII infusion did not change food intake from the control level after the initial tachyphylaxis.

    In plain wordsIn rats, continuous melanotan II no longer changed food intake from the control level after the first effect wore off.

    Peptide
    Melanotan II
    Outcome
    No significant changeFood intake with continuous MTII
    Study

    ratn: not reported in source

    F344/BN rats
    Comparator
    Vehicle
    Outcome group
    Appetite and food intake · Metabolic and weight
    Studied dose
    Dose not stated · intracerebroventricular (lateral ventricle, mini pump)As given in this study (rat).

    Source sentences

    Summary
    while continuation of MTII supplement in the MTII-On group did not change food intake from the control level.
    2 context sentences
    Summary · context
    Half the MTII-infused rats were then given vehicle (MTII-On/Off), while the remaining received fresh MTII (MTII-On) for 10 days.
    Summary · context
    F344/BN rats were infused with MTII or vehicle into the lateral ventricle by mini pump for 14 days.
  4. 04AnimalAnimal study (in vivo)Efficacy outcome

    In rats, body weights decreased similarly in the intermittent and continuous MTII groups at day 30.

    In plain wordsIn rats, body weight fell by a similar amount with intermittent and with continuous melanotan II.

    Peptide
    Melanotan II
    Outcome
    DecreaseBody weight at day 30
    Study

    ratn: not reported in source

    F344/BN rats
    Comparator
    Vehicle
    Outcome group
    Body weight · Metabolic and weight
    Studied dose
    Dose not stated · intracerebroventricular (lateral ventricle, mini pump)As given in this study (rat).

    Source sentences

    Summary
    Body weights decreased similarly in both MTII groups at termination (day 30).
    1 context sentence
    Summary · context
    F344/BN rats were infused with MTII or vehicle into the lateral ventricle by mini pump for 14 days.
  5. 05AnimalAnimal study (in vivo)Efficacy outcome

    In rats, adiposity was reduced by 80% in both MTII groups.

    In plain wordsIn rats, body fat fell by 80% with either melanotan II schedule.

    Peptide
    Melanotan II
    Outcome
    DecreaseAdiposity
    Study

    ratn: not reported in source

    F344/BN rats
    Comparator
    Vehicle
    Outcome group
    Body weight · Metabolic and weight
    Studied dose
    Dose not stated · intracerebroventricular (lateral ventricle, mini pump)As given in this study (rat).

    Measurements

    Adiposity reduction
    80%
    both MTII groups

    Source sentences

    Summary
    adiposity reduced by 80% in both MTII groups.
    1 context sentence
    Summary · context
    F344/BN rats were infused with MTII or vehicle into the lateral ventricle by mini pump for 14 days.
  6. 06AnimalAnimal study (in vivo)Mechanism

    In rats, hypothalamic MC3 receptor, AgRP and POMC expression did not change with MTII.

    In plain wordsIn rats, melanotan II did not change the activity of three feeding-related genes in the hypothalamus.

    Peptide
    Melanotan II
    Outcome
    No significant changeHypothalamic MC3 receptor, AgRP and POMC expression
    Study

    ratn: not reported in source

    F344/BN rats
    Comparator
    Vehicle
    Outcome group
    Receptor activity and mechanism · Metabolic and weight
    Studied dose
    Dose not stated · intracerebroventricular (lateral ventricle, mini pump)As given in this study (rat).

    Source sentences

    Summary
    Hypothalamic MC3 receptor, AgRP, and POMC expressions were unchanged
    1 context sentence
    Summary · context
    F344/BN rats were infused with MTII or vehicle into the lateral ventricle by mini pump for 14 days.
  7. 07AnimalAnimal study (in vivo)Mechanism

    In rats, hypothalamic MC4 receptor expression was diminished by 25% in both MTII groups.

    In plain wordsIn rats, melanotan II lowered activity of the MC4 receptor gene in the hypothalamus by 25%.

    Peptide
    Melanotan II
    Outcome
    DecreaseHypothalamic MC4 receptor expression
    Study

    ratn: not reported in source

    F344/BN rats
    Comparator
    Vehicle
    Outcome group
    Receptor activity and mechanism · Metabolic and weight
    Studied dose
    Dose not stated · intracerebroventricular (lateral ventricle, mini pump)As given in this study (rat).

    Measurements

    MC4 receptor expression reduction
    25%
    both MTII groups

    Source sentences

    Summary
    MC4 receptor expression was diminished by 25%, and adiposity reduced by 80% in both MTII groups.
    1 context sentence
    Summary · context
    F344/BN rats were infused with MTII or vehicle into the lateral ventricle by mini pump for 14 days.
  8. 08AnimalAnimal study (in vivo)Mechanism

    In rats, acetyl-CoA carboxylase 1 phosphorylation in perirenal fat rose by over 10 fold with either MTII treatment.

    In plain wordsIn rats, either melanotan II schedule raised a fat-metabolism marker in kidney-area fat by more than 10 times.

    Peptide
    Melanotan II
    Outcome
    IncreaseAcetyl-CoA carboxylase 1 phosphorylation in perirenal fat
    Study

    ratn: not reported in source

    F344/BN rats
    Comparator
    Vehicle
    Outcome group
    Receptor activity and mechanism · Metabolic and weight
    Studied dose
    Dose not stated · intracerebroventricular (lateral ventricle, mini pump)As given in this study (rat).

    Measurements

    ACC1 phosphorylation fold increase
    > 10 fold
    perirenal fat

    Source sentences

    Summary
    Acetyl-CoA carboxylase 1 phosphorylation was elevated in perirenal fat by over 10 fold with either MTII treatment.
    1 context sentence
    Summary · context
    F344/BN rats were infused with MTII or vehicle into the lateral ventricle by mini pump for 14 days.

AI wrote and checked these results. AI can make mistakes, so check important results against the source.

Version history

PepBank keeps every version of the data on this study. Status changes from Retraction Watch, Europe PMC and Crossref are listed with their source.

  1. Version 2Current

    10 Oct 2026, 09:43 UTC

    Study results updated

  2. Version 1

    9 Oct 2026, 03:04 UTC

    First added · source update from Europe PMC

Subjects

Terms as the source lists them.

PepBank is a research reference. Talk to a doctor before you use any peptide.